Silicon is capable of extensive catenation. Thus, linear dimethyl polysilanes containing chains of up to twenty four directly bonded silicon atoms, high molecular weight polymers based on chains of silicon atoms and cyclopolysilanes with as many as thirty five silicon atoms in a single ring have all been prepared. (See. R. West in G. Wilkinson, F. G. A. Stone and E. W. Abel Eds., "Comprehensive Organo-metallic Chemistry," Pergamon Press, New York, N.Y., 1982, vol. 2, chapter 9.4.). Such materials can be degraded by application of heat (pyrolyzed) to give SiC ceramic materials, including in some cases strong SiC fibers (U.S. Pat. Nos. 4,260,780 and 4,276,424). Furthermore, some of the polysilanes can themselves be formed into films or fibers or molded, cast or spun from hot melt or from solution (U.S. Pat. No. 4,324,901).